I posted this in remodeling before realizing there was a windows forum.

In an effort to salvage my proposed addition (estimates came back too migh), I was looking on craigslist for materials. There are quite a few never-installed Andersen and Pella doors and windows for sale by people wh changed their minds before insallation. Does anyone know if the warranty starts at purchase or at install of these items? If I buy from a private seller, do I lose the warranty? Also, can I claim the tax credit if the door meet the published energy requirements?

thank you!